Commands by dcabanis (20)

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generate random password
for Mac OS X

Pronounce an English word using Dictionary.com
This one uses dictionary.com

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

hard disk information - Model/serial no.
Get the hard disk information with out shutting down and opening the system. It gives information on model no., serial no., cylinders/heads/sectors, and the supported features of the hard disk.

Diff two directories by finding and comparing the md5 checksums of their contents.
Compute the md5 checksums for the contents of two mirrored directories, then sort and diff the results. If everything matches, nothing is returned. Otherwise, any checksums which do not match, or which exist in one tree but not the other, are returned. As you might imagine, the output is useful only if no errors are found, because only the checksums, not filenames, are returned. I hope to address this, or that someone else will!

Clear your history saved into .bash_history file!
Note the space before the command; that prevents your history eliminating command from being recorded. ' history -c && rm -f ~/.bash_history' Both steps are needed. 'history -c' clears what you see in the history command. 'rm -f ~/.bash_history' deletes the history file in your home directory.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Ping sweep without NMAP
Waits for all pings to complete and returns ip with mac address

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Control ssh connection
SSH can be controlled trough an ~ escape sequence. Example, to terminate the current ssh connection, type a newline, then the ~ character, and last a . character. This is useful eg when an ssh connection hangs after you reboot a machine and the connection hangs.


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